instantaneous

adjective

in·​stan·​ta·​neous ˌin(t)-stən-ˈtā-nē-əs 

-nyəs

1

: done, occurring, or acting without any perceptible duration of time

death was instantaneous

2

: done without any delay being purposely introduced

took instantaneous corrective action

3

: occurring or present at a particular instant

instantaneous velocity

instantaneity

ˌin-ˌstan-tə-ˈnē-ə-tē 

ˌin(t)-stən-tə-ˈnē-

noun

instantaneously

ˌin(t)-stən-ˈtā-nē-əs-lē 

-nyəs-lē

adverb

instantaneousness noun

Synonyms

• immediate
• instant
• split-second
• straightaway

Examples of instantaneous in a Sentence

We got an almost instantaneous response from the company.

the thunder following the flash of lightning was nearly instantaneous

Recent Examples on the Web

With the synergy between them, the desire to work together was instantaneous. —Tiffany Leigh, Forbes, 16 Sep. 2024

Silicon Valley’s intensely partisan discourse continues, and the memes were instantaneous. —Allie Garfinkle, Fortune, 11 Sep. 2024

That relief likely wouldn’t be instantaneous but would probably take many months to wind through the economy, economists said. —Greg Iacurci, CNBC, 6 Sep. 2024

Cobre partners with financial institutions and opens accounts where its customers and their payees bank (as transfers within the same bank are instantaneous), and keeps an internal ledger of the money movement. —Lucinda Shen, Axios, 5 Sep. 2024

Word History

Etymology

borrowed from Medieval Latin instantāneus, from instant-, instans "moment, point of time," + Latin -āneus, suffix forming adjectives from temporal adverbs — more at instant entry 1

Note: Regarding the suffix -āneus see the etymology and note at spontaneous.

First Known Use

1651, in the meaning defined at sense 1

Kids Definition

instantaneous

adjective

in·​stan·​ta·​neous ˌin(t)-stən-ˈtā-nē-əs 

-nyəs

1

: happening in an instant

2

: done without delay

instantaneously adverb

instantaneousness noun